Mercenaries. Not undercover operatives that are still part of the Armed Forces, but private hired mercenaries. To my knowledge Contracted operatives arent used for kills by any country. PMC's or Private military contractors are usually used to provide security role like Wagner of Russia or Academy in US. Pakistan or India don't have any PMC.
Correct me if I’m wrong.
Divergent
Pakistan has a number of PSC: Private Security Contractors, the biggest being Askari Guards and Wackenhut, private security in Pakistan is big business as of 2014 in Karachi alone, there are reportedly 55,000 private security guards, as compared to an operational police strength of 27,000.
There are three layers of guards:
When people think of security guarding in pakistan they often think of this:
But there is another element of security in Pakistan, the ex- military special forces kind, these guys are the bee's knees and know their job very well. An example of retired ex special forces private security contractors in Pakistan:
There are also bonafide private ex special forces trainers in Pakistan which charge big bucks for specialist training in Pakistan.
Pakistan also has a number of more shady security companies which are operating as PMCs. The last one to be shut down was Inter-risk based in Islamabad which worked for Halliburton and Xe. It was run by a retired Pakistani Army Captain called Zaidi, here is a picture of the man being arrested by Islamabad Police:
http://www.washingtonpost.com/wp-dyn/content/article/2009/09/19/AR2009091902453.html
There have been numerous other operations which were shut down by the intelligence services for obvious reasons. Pakistan exports ex-army vets to countries in the middle east and this is no secret:
https://www.voanews.com/a/pakistani-veterans-beef-up-bahrain-security-forces-128031883/167892.html
Out of the 200+ private security agencies in Pakistan only 9 have signed the "International Code of Conduct on Private Security"
https://www.icoca.ch/en/membership?private_security_companies[companies]=companies&area_of_operation=all&headquarter_country=174&keywords=&op=Search&view_type=map&form_build_id=form-4kZNwqq8kkJFsj1nduk6xA2YvT9MQQqejL1FGRavTYU&form_id=_search_for_members_filter_form#search_for_members_list
There are also companies in Pakistan which hire ex military vets for projects in the Middle East:
Hope this helps your inquiry.